The threat of infectious diseases, in particular AIDS and hepatitis B, is very prevalent today in hospitals and doctors' offices as a result of the use of hypodermic syringes. The Centers for Disease Control in Atlanta has extensively studied accidental syringe sticking incidents and have logged where most of the accidents occur and to whom. The Centers' records indicate that nurses experience more incidents than most other medical personnel.
Recovering the needle with the plastic tip cover provided with the syringe after use has not solved the problem because the cover can slip off or a person can be stuck by merely attempting to place the cover on the needle. Other means presently utilized for the disposal of used syringes still leave the steel of the hypodermic needle on the syringe, thereby exposing the waste handlers to the possibility of being pricked. The present syringe disposal systems are also very expensive.
The prior art includes the apparatus disclosed in U.S. Pat. No. 4,628,169 which describes an apparatus for melting only the tip of the needle, with the remainder of the metal on the syringe being detached by a separate operation. The remaining metal portion may still be contaminated. That system still leaves the possibility of the person collecting the remaining needle portion being exposed to microorganisms. Also, any infectious fluids are still available to flow out of the now-open plastic portion of the syringe.
U.S. Pat. No. 4,877,934 discloses a needle destroying apparatus which utilizes converging electrodes. The hypodermic syringe is inserted into the apparatus in a vertical orientation and is either slid onto a bottom electrode ramp or an electrode that can slide toward the bottom electrode thereby destroying the needle. However, because of the vertical orientation of the needle as it is inserted into the apparatus, the burnt needle tends to bend away from the ramp and loses contact with the bottom electrode. In addition, because of the vertical orientation, the burnt needle tends to collect on the bottom electrode thereby fouling the surface of the bottom electrode.
U.S. Pat. No. 5,736,706 teaches a device that both melts the needle and shears the needle portion from the syringe. This particular patent is commonly owned with the present application and shares some of the same features. It does not, however, accept the newer generation of pen-type hypodermic syringes.
What is needed is a needle destruction apparatus that is easy to operate and will reliably and efficiently destroy the needle of a pen-type hypodermic syringe. What is further needed is an apparatus that can be used in the clinic that can be used for long periods of time before it has to be taken apart and cleaned. An apparatus is needed that will treat used syringes to prevent storage of live viruses and other microorganisms in unsealed containers at room temperature, causing unwanted aerosol vapor to contaminate room air breathed by health care workers and patients.